Battery pack

ABSTRACT

A battery pack is loaded and unloaded to and from a battery mounting portion while sliding one surface thereof in the battery mounting portion. The one surface is provided with a pair of insertion guide grooves extending along the sliding direction and spaced from each other in the sliding direction. Each of the insertion guide grooves has an end portion fronting on a side surface of a battery main body.

CROSS REFERENCES TO RELATED APPLICATIONS

The present invention contains subject matter related to Japanese PatentApplication JP 2007-095325 filed in the Japan Patent Office on Mar. 30,2007, the entire contents of which being incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a battery pack which is formed so thatit can be attached to and detached from an electronic apparatus and inwhich battery cells for supplying driving electric power to theapparatus main body is contained.

2. Description of the Related Art

As portable electronic apparatuses such as digital still cameras andcamcorders, there have widely been used those which are provided with abattery mounting portion such that a battery pack loaded with batterycells is attached thereto and detached therefrom by the user himself. Atthe time of using such an apparatus, a previously charged battery packis attached to the battery mounting portion, and, when the battery hasrun down, the battery is replaced with a separately charged sparebattery pack, whereby the apparatus can be used for a long time.

Each of this kind of battery packs is provided with terminal portionscorresponding to electrode terminals disposed on the battery mountingportion side, and is attached to the battery mounting portion in such amanner that the terminal portions are mated to the electrode terminals.Here, in business-use camcorders and the like, the battery capacityrequired is higher and the battery pack is hence larger in size andweight, since the use time is longer and the use frequency is higher, ascompared with private-use camcorders and the like. In the business-usecamcorders and the like, therefore, if chattering is present between thebattery pack and the battery mounting portion to which the battery packis mounted, the loads exerted on the battery pack and the batterymounting portion due to vibrations on the apparatus main body sideduring use would be high.

On the other hand, in the case where a recess shape for contrivingengagement with a protrusion shape projectingly provided at the batterymounting portion is formed in a large size in a mount surface, formounting to the battery mounting portion, of the battery pack in orderto prevent the chattering, the identification label adhering region ofthe mount surface would be narrowed, and the size of the circuit boarddisposed on the inner surface side of the mount surface and anelectronic part mounting region would be limited.

Patent Document 1

-   Japanese Patent Laid-open No. 2006-228471

SUMMARY OF THE INVENTION

There is a need for a battery pack with which it is possible to preventchattering between the battery pack, tending to be enlarged in size andweight, and a battery pack mounting portion, to realize thechattering-preventive mechanism in a space-saving manner, and toeffectively utilize a mount surface to be mounted to the batterymounting portion.

According to an embodiment of the present invention, there is provided abattery pack which is loaded and unloaded to and from a battery mountingportion while sliding one surface thereof in the battery mountingportion, wherein the one surface is provided with a pair of insertionguide grooves extending along the sliding direction and spaced from eachother in the sliding direction; and each of the insertion guide grooveshas an end portion fronting on a side surface of a battery main body.

In accordance with the battery pack based on the embodiment according tothe present invention, the operations of loading and unloading thebattery pack to and from the battery mounting portion are guided by thepair of insertion guide grooves, and the battery pack mounted in thebattery pack mounting portion is prevented from chattering in adirection orthogonal to the sliding direction. In addition, since theinsertion guide grooves in the battery pack are formed to be spaced fromeach other in the sliding direction, a substantially central area of theone surface is secured to be wide, so that a large-sized single sheet ofidentification label can be adhered thereto, and, further, a circuitboard disposed on the inner side of the one surface can also have a wideregion for mounting electronic parts.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are perspective views of a large size battery;

FIG. 2 is an exploded perspective view of the battery;

FIGS. 3A and 3B are perspective views of a small size battery;

FIG. 4 is a side view of a camcorder in which a battery is to bemounted;

FIG. 5 is a perspective view of the camcorder with the battery mountedtherein;

FIGS. 6A and 6B are bottom views each showing the bottom surface of ahousing, wherein FIG. 6A shows the large size battery, while FIG. 6Bshows the small size battery;

FIG. 7 is a sectional view showing a circuit board disposed inside thehousing;

FIG. 8 is a perspective view showing a battery mounting portion;

FIG. 9 is a perspective view showing a battery to be attached to thebattery mounting portion;

FIGS. 11A and 10B are side views showing a detection recess and a lockrecess, respectively;

FIGS. 11A and 11B each show a side view of the housing in the case wherea battery of a wrong size is erroneously inserted into the batterymounting portion;

FIG. 12 is a perspective view showing terminal portions in a partly cutstate;

FIG. 13 is a perspective view showing the terminal portion in a partlycut state;

FIG. 14 is a perspective view showing the manner in which a terminalcase connected to battery cells and the circuit board is contained in alower case;

FIG. 15 is a perspective view of the terminal portions formed in thehousing, as viewed from inside;

FIG. 16 is a front view of the terminal portions;

FIGS. 17A and 17B show a terminal case connected to the battery cellsand the circuit board, wherein FIG. 17A is a front view, and FIG. 17B isa bottom view;

FIG. 18 is an exploded perspective view of a battery containing portion;

FIG. 19 is a perspective view of the battery containing portion;

FIGS. 20A and 20B are perspective views of a terminal plate, whereinFIG. 20A shows a one surface side, and FIG. 20B shows the bottom surfaceside;

FIG. 21 is a perspective view of a containing case;

FIG. 22 is a perspective view of a support plate;

FIG. 23 is a block diagram of a residual capacity display portion;

FIG. 24 is a table showing the ON/OFF conditions of the residualcapacity display portion; and

FIG. 25 is a flow chart showing the flow of display in the residualcapacity display portion.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, a battery pack based on embodiments according to the presentinvention will be described in detail below, referring to the drawings.As shown in FIGS. 1A and 1B, the battery pack 1 has a housing 2containing battery cells therein and formed in a substantiallyrectangular shape, with terminal holes in a front surface thereof. Asshown in FIG. 2, the housing 2 has an upper cover 3 and a lower case 4abuttingly coupled to each other, and a plurality of battery cells 8composed of lithium ion secondary batteries and a circuit board 9 onwhich a protective circuit, an SMBus (System Management Bus) controller,an ID resistor and the like are mounted and which is provided with anSMBus line are contained in the housing 2. Besides, as shown in FIGS.1A, 1B, 3A and 3B, the battery packs 1 are prepared in two kinds,namely, for example, large size battery packs 1 a and small size batterypacks 1 b made to be different from each other in electric capacityaccording to the number of the battery cells 8 to be contained in thehousing 2, and the two kinds of the battery packs 1 are used selectivelyaccording to the electronic apparatus for which they are used.Specifically, the large size battery pack 1 a contains eight batterycells in two rows and four layers, while the small size battery pack 1 bcontains four battery cells in two rows and two layers.

Of the housing 2 thus containing the battery cells, a lower surface 2 ais made to be a mount surface which is mounted on a battery mountingportion 5 on the electronic apparatus side, and first to fifth terminalportions 6 a to 6 e are disposed fronting on a front surface 2 b whichis continuous with the mount surface. Terminals formed at the terminalportions 6 a to 6 e have respectively predetermined functions; morespecifically, the first terminal portion 6 a is a positive electrodeterminal of the battery pack 1, the second terminal portion 6 b is aclock line terminal in the SMBus line, the third terminal portion 6 c isa data line terminal in the SMBus line, the fourth terminal portion 6 dis an ID terminal connected with an ID resistor, and the fifth terminalportion 6 e is a negative electrode terminal of the battery pack 1.

In mounting the battery pack 1 in the electronic apparatus, it isinserted into the battery mounting portion 5 on the electronic apparatusside, with the lower surface 2 a as an insertion end, and, after thelower surface 2 a comes into abutment on a bottom surface 5 a of thebattery mounting portion 5, the battery pack 1 is slid toward the sideof the front surface 2 b, whereby lock recesses 55 and 56 provided inboth side surfaces 2 c and 2 d of the housing 2 are locked by lockprotrusions 70 formed in the battery mounting portion 5, resulting inthat the battery pack 1 is mounted in the electronic apparatus. Todetach the battery pack 1 from the electronic apparatus, the batterypack 1 is slid toward the side of a back surface 2 e opposite to thefront surface 2 b of the housing 2, and then the battery pack 1 ispulled up toward the side of an upper surface 2 f opposite to the lowersurface 2 a, whereby the battery pack 1 is detached.

Examples of the electronic apparatus for which the battery pack 1 isused include a camcorder 7 shown in FIG. 4. The camcorder 7 is one forbusiness use, and is provided with the battery mounting portion 5 at aback surface 7 a of a main body thereof. The battery mounting portion 5is so set that only the large size battery pack 1 a having aconsiderable battery capacity can be mounted therein, in view of the usetime and frequency of the business-use camcorder 7 and the like factors.

As shown in FIG. 5, the battery pack 1 is inserted into the batterymounting portion 5 of the camcorder 7 in the direction of an arrow D inthe figure along the right side of a back surface 7 a of the camcorder7, with its lower surface 2 a as an insertion end, until it comes to aloading/unloading position where the lower surface 2 a abuts on thebottom surface 5 a of the battery mounting portion 5. Next, the batterypack 1 inserted to the loading/unloading position inside the batterymounting portion 5 is slid in the direction of an arrow S, namely,leftwards in FIG. 5, until it comes to a mounting position whereterminal pins 101 fronting on the inside of the battery mounting portion5 are inserted in the terminal portions 6 provided at the front surface2 b of the battery pack 1 and, simultaneously, the lock recesses 55 and56 provided in both side surfaces 2 c and 2 d of the battery pack 1 arelocked by the lock protrusions 70, whereby the mounting is completed.

Incidentally, the battery cells 8 are contained in two rows in thebattery pack 1, irrespectively of whether the battery pack 1 is thelarge size battery pack 1 a or the small size battery pack 1 b;therefore, the area of the lower surface 2 a serving as a mount surfacefor mounting into the battery mounting portion 5 is set substantiallythe area occupied by two battery cells 8 disposed side by side.Accordingly, even in the camcorder 7 for which the large size batterypack 1 a is used, the area of the battery mounting portion 5 need not beso large, and other switches can be arranged at the back surface 7 a ofthe main body of the camcorder 7.

Now, the configuration of the battery pack 1 will be specificallydescribed below. The housing 2 of the battery pack 1 is formed from asynthetic resin. As shown in FIGS. 1B and 3B, one side surface of thebattery pack 1 which is adjacent to the front surface 2 b and the backsurface 2 e and which is directed vertically upwards at the time ofmounting the battery pack 1 into the battery mounting portion 5 isprovided with an identification portion 10 for identifying grippingsurfaces according to the mounting direction. In addition, the frontsurface 2 b and the back surface 2 e of the housing 2 are provided withanti-slip portions 11 at positions to be gripped by the user. With theidentification portion 10 and the anti-slip portion 11 thus formed, itcan be seen if the housing 2 is gripped correctly in mounting thebattery pack 1 into the battery mounting portion 5. Besides, the housing2 can be gripped assuredly even where the housing 2 has an increasedweight.

Specifically, at the time of mounting the battery pack 1 into thebattery mounting portion 5, the battery pack 1 is inserted in such amanner that its lower surface 2 a serving as the mount surface is usedas the insertion end, and the front surface 2 b provided with theterminal portions 6 is slid in a horizontal direction, asabove-mentioned. Therefore, it would be necessary for the user to gripthe battery pack 1 in the condition where the front surface 2 b isdirected toward the terminal side in the battery mounting portion 5.

The identification portion 10 is for permitting the user to discriminatethe gripping surfaces of the housing 2 at the time of mounting thebattery pack 1 into the battery mounting portion 5. The identificationportion 10 is formed by a method in which one side surface 2 c isprovided with a recessed surface portion 10 a, the inside of therecessed surface portion 10 a is grained, and, further, the recessedsurface portion 10 a is provided with grains composed of protrusionsextending in the front-rear direction. When the user grips the batterypack 1 with his right hand, the index finger or the middle finger is puton the one side surface 2 c so that the identification portion 10 makescontact with the fingertip; as a result, it can be intuitively perceivedthat the housing 2 is correctly gripped with its one side surface 2 cdirected vertically upwards, and the sliding direction upon insertion ofthe housing 2 into the battery mounting portion 5 can also be graspedintuitively.

In addition, as above-mentioned, where the battery pack 1 is the largesize battery pack 1 a, a total of eight battery cells 8 are contained intwo rows and four layers, and where the battery pack 1 is the small sizebattery pack 1 b, a total of four battery cells 8 are contained in tworows and two layers. As a result, the large size battery pack 1 a isabout 550 g in weight, while the small size battery pack 1 b is 300 g inweight, heavier than a private-use battery in which battery cells arecontained in two rows and one layer. Accordingly, the battery packsshould be prevented from slipping down from the user's hand.

The anti-slip portions 11 formed in the front surface 2 b and the backsurface 2 e are for preventing the slipping-down of the battery pack 1by making the housing 2 easier to grip by the user's hand at the time ofmounting the battery pack 1 into the battery mounting portion 5. Theanti-slip portions 11 are formed by forming recessed surface portions 11a at upper portions of the front surface 2 b and the back surface 2 e,and graining the inside of the recessed surface portions 11 a. Whengripping the battery pack 1 with the right hand, the user put the thumbon the anti-slip portion 11 in the front surface 2 b, and put the middlefinger or the third finger and the little finger on the anti-slipportion 11 in the back surface 2 e, whereby the rugged surfaces of theanti-slip portions 11 function to give frictional resistance, ensuringthat the housing 2 can be held securely without slipping. Incidentally,as the shape of the grains imparted to the recessed surface portions 11a of the anti-slip portions 11, any of a variety of shapes can beadopted.

Incidentally, the housing 2 is provided with a grain different fromthose of the identification portion 10 and the anti-slip portions 11, inother regions than the identification portion 10 and the anti-slipportions 11 of the upper cover 3.

Now, the configuration of the lower surface 2 a serving as the mountsurface for mounting into the battery mounting portion 5 will bedescribed below. The lower surface 2 a is provided with a pair ofinsertion guide grooves 15 and 16 which extend along and are spaced fromeach other along the direction of sliding between the mounting positionand the lading/unloading position inside the battery mounting portion 5,and other region than the insertion guide grooves 15 and 16 is used as aregion for adhering an identification label 14 (see FIG. 2). Into theinsertion guide grooves 15 and 16, guide protrusions 30 and 31projectingly provided on the bottom surface 5 a of the battery mountingportion 5 are inserted, whereby the operations of mounting anddismounting the housing 2 are guided, and the housing 2 mounted in thebattery mounting portion 5 is prevented from chattering in the directionof both side surfaces 2 c and 2 d.

As shown in FIGS. 6A and 6B, the housing 2 has the lower surface 2 aprovided with the insertion guide grooves 15 and 16 spaced from eachother along the sliding direction, whereby a substantially centralportion can be made to be wide, and a side adhering region for theidentification label 14 can be secured. In addition, since the lowersurface of the housing 2 is not cut up into left and right portions bythe insertion guide grooves 15 and 16, as shown in FIG. 2, a largesingle identification label 14 formed in a substantially H shape can beadhered.

Furthermore, since the housing 2 has the lower surface 2 a provided withthe insertion guide grooves 15 and 16 spaced from each other along thesliding direction, as shown in FIG. 7, that region of the inside surfaceof the lower surface 2 a which is occupied by protrusions present due tothe insertion guide grooves 15 and 16 projecting to the inside of thehousing 2 can be minimized. Therefore, in the housing 2, a wideelectronic part mounting region and a wide patterning region can besecured on the lower surface 2 a side of the circuit board 9 disposed onthe inside of the lower surface 2 a, and efficient use of space can berealized.

The insertion guide grooves 15 and 16 are formed substantially in thecenter in the width direction of the lower surface 2 a along thefront-rear direction. In addition, the front surface side insertionguide groove 15 formed on the front surface 2 b side has an end facefronting on a lower portion of the front surface 2 b, while the backsurface side insertion guide groove 16 formed on the back surface 2 eside has an end face fronting on a lower portion of the back surface 2 eand is provided with a lock recess 17 by which a lock piece 35 providedin the battery mounting portion 5 is locked.

The front surface side insertion guide groove 15 is provided with anL-shaped opening 18 where its insertion end fronting on the frontsurface 2 b is opened in a substantially L shape, and a front surfaceside guide groove portion 20 continued through a stepped portion 19formed on the back surface side relative to the L-shaped opening 18. Asshown in FIG. 8, a front surface side guide protrusion 30 formed at thedeepest portion in the sliding direction of the battery mounting portion5 is passed through the front surface side insertion guide groove 15.The front surface side guide protrusion 30 is provided with a frontsurface side protruding bar 32 to be inserted in the front surface sideguide groove portion 20, and a lock protrusion 33 substantially L-shapedin section which is formed on the deeper side of the front surface sideprotruding bar 32 and which is locked by the L-shaped opening 18. Thefront surface side insertion guide groove 15 is so formed that when thehousing 2 is inserted to the loading/unloading position in the batterymounting portion 5 and is slid toward the front surface 2 b side to themounting position, the front surface side protruding bar 32 of the frontsurface side guide protrusion 30 is inserted in the front surface sideguide groove portion 20, an end face of the lock protrusion 33 abuts onthe stepped portion 19, and the lock protrusion 33 is locked by theL-shaped opening 18.

The back surface side insertion guide groove 16 is provided with thelock recess 17 for locking the lock piece 35, by forming an end portionfronting on the back surface 2 e in a substantially rectangular shape,and with a back surface side guide groove portion 21 formed on the frontsurface side relative to the lock recess 17. The back surface side guidegroove portion 21 is formed in line with the front surface side guidegroove portion 20. In addition, the lock recess 17 is formed to be widerthan the back surface side guide groove portion 21, and is formed to becontinuous with the back surface side guide groove portion 21, whereby alock wall 22 for locking the lock piece 35 is provided on the frontsurface side of the housing 2.

Into the back surface side insertion guide groove 16, a back surfaceside guide protrusion 31 formed in the battery mounting portion 5 isinserted. The back surface side guide protrusion 31 is provided with aback surface side protruding bar 34 to be passed through the backsurface side guide groove portion 21, and the lock piece 35 to be lockedby the lock recess 17. The back surface side protruding bar 34 is formedin line with the front surface side protruding bar 32. Besides, the lockpiece 35 is inserted in the battery mounting portion 5 through a lockhole 36 opened in the bottom surface 5 a of the battery mounting portion5, as shown in FIG. 8, whereby its tip portion is brought into abutmenton the lock wall 22. The lock piece 35 can be turned into and out of thebattery mounting portion 5 by a turning mechanism 40.

The turning mechanism 40 is mounted to a back surface wall of thebattery mounting portion 5, and includes a support plate 41 forsupporting the lock piece 35, a push bar 42 for pushing the lock piece35, and an operating button 43 for operating the push bar 42. Thesupport plate 41 supports a turning shaft 44 passed through a turningbearing 35 a formed at a rear end portion of the lock piece 35. Inaddition, the turning shaft 44 is fitted with a coil spring 45 of whichone end is locked on the support plate 41 and the other end is locked onthe lock piece 35. This ensures that the lock piece 35 is constantlyturningly urged by the coil spring 45 in the direction of an arrow L inFIG. 8 so that its tip portion is made to front on the inside of thebattery mounting portion 5 through the lock hole 36. The push bar 42 forpushing the lock piece 35 is for turning the lock piece 35, which isurged toward the direction of the arrow L, in the direction opposite tothe arrow L, and is supported by the support plate 41 so as to bemovable up and down between the support plate 41 and a side surface ofthe battery mounting portion 5. The push bar 42 abutting on the lockpiece 35 at its one end is provided with an inclined surface portion 42a at its other end opposite to the one end, and the operating button 43abuts on the inclined surface portion 42 a. The operating button 43 isfor turning the lock piece 35 in the direction opposite to the arrow Lby sliding the push bar 42 through pushing the inclined surface portion42 a of the push bar 42. The operating button 43 is supported on a sidesurface of the battery mounting portion 5 by a support member (notshown), and is constantly urged by the coil spring 45 in such adirection that its tip portion is spaced away from the inclined surfaceportion 42 a of the push bar 42.

The back surface side insertion guide groove 16 is so configured that,when the housing 2 is inserted into the battery mounting portion 5 andis slid toward the front surface 2 b side, the back surface sideprotruding bar 34 is inserted in the back surface side guide grooveportion 21, and the lock piece 35 is inserted in the lock recess 17 soas to abut on the lock wall 22 formed between the lock recess 17 and thefront surface side guide groove portion 20.

As a result, the housing 2 is guided in the sliding inside the batterymounting portion 5, and is prevented from chattering in a directionorthogonal to the sliding direction. More specifically, with the frontsurface side guide protrusion 30 inserted in the front surface sideinsertion guide groove 15 and with the back surface side guideprotrusion 31 inserted in the back surface side insertion guide groove16, the housing 2 is prevented from chattering in the direction of bothside surfaces 2 c and 2 d.

In addition, with the lock protrusion 33 engaged with the L-shapedopening 18, the housing 2 is prevented from chattering in the directionof both side surfaces 2 c and 2 d and from chattering in the directionof the upper and lower surfaces 2 f and 2 a. Therefore, the housing 2can be secured in reliability of connection to the battery mountingportion 5. Besides, with the L-shaped opening 18 is made to be exposedside by side with the terminal portions 6 a to 6 e, stresses pertainingto the terminal portions 6 a to 6 e can be suppressed, and reliabilityof electrical connection can be secured.

Furthermore, when the housing 2 is slid to the mounting position, thelock piece 35 abuts on the lock wall 22, whereby the housing 2 isprevented from sliding in the direction of the back surface 2 e, namely,in the direction from the mounting position toward the loading/unloadingposition, and is prevented from slipping off the battery mountingportion 5 due to vibration, shock or the like. In addition, the housing2 is prevented from chattering in the battery mounting portion 5, alsoby the locking of the lock piece 35 in the lock recess 17.

Incidentally, in detaching (unloading) the battery pack 1 from thebattery mounting portion 5, the operating button 43 of the turningmechanism 40 is depressed, upon which the tip of the operating button 43pushes the inclined surface portion 42 a of the push bar 42, and thepush bar 42 is slid toward the bottom surface 5 a side. As a result, thelock piece 35 pushed by the push bar 42 so as to be urged turningly inthe direction opposite to the arrow L, so that the lock piece 35 isretracted from the inside of the battery mounting portion 5, and isdisengaged from the lock recess 17 of the housing 2. This results inthat the housing 2 can be slid in the direction of the back surface 2 e.

Thus, the back surface side insertion guide groove 16 is provided withthe lock recess 17 continuous with the back surface side guide grooveportion 21, whereby it is promised that the housing 2 is prevented fromchattering in the battery mounting portion 5 and from sliding in thedirection of the back surface 2 e. In addition, that region of the lowersurface 2 a which is occupied by the back surface side insertion guidegroove 16 can be reduced, and efficient utilization of the lower surface2 a can be contrived. Therefore, the housing 2 is provided with a widerregion for adhering the identification label 14 onto the lower surface 2a, and with an enlarged region for disposing the circuit board 9 on theinside of the lower surface 2 a.

Now, the configuration of both side surfaces 2 c and 2 d of the housing2 will be described below. The housing 2 is provided with a detectionrecess or recesses 50 for detecting the kind of the battery pack 1, atan edge or edges formed between the lower surface 2 a and one or both ofthe side surfaces 2 c and 2 d. As above-mentioned, the battery packs 1prepared are classified into the large size battery packs 1 a and thesmall size battery packs 1 b, according to the magnitude of batterycapacity. In the large size battery pack 1 a, the detection recesses 50are provided respectively in both side surfaces 2 c and 2 d, as shown inFIG. 6A; in the small size battery pack 1 b, on the other hand, thedetection recess 50 is provided only on the side of the other sidesurface 2 d, as shown in FIG. 6B.

In addition, as shown in FIG. 9, the battery mounting portion 5 isprovided with mis-insertion preventive engaging protrusions 51corresponding to the detection recess 50, on side surfaces opposed tothe side surfaces 2 c and 2 d. With such engaging protrusions 51projectingly provided, mis-mounting of a battery pack of anon-compatible size can be obviated. Specifically, since the large sizebattery pack 1 a is provided with a pair of the detection recesses 50 inboth side surfaces 2 c and 2 d, the battery mounting portion 5 of anelectronic apparatus corresponding to the large size battery pack 1 a isprovided with a pair of the engaging protrusions 51 for engagement withboth detection recesses, whereby the small size battery pack 1 bprovided with the detection recess 50 only in the other side surface 2 dcan be prevented from being erroneously mounted into the batterymounting portion 5 in consideration. In this case, the engagingprotrusion 51 projectingly provided on the side surface opposite to theother side surface 2 d of the small size battery pack 1 b interfereswith the edge formed between the other side surface 2 d and the lowersurface 2 a of the housing 2, whereby the small size battery pack 1 b isprevented from being mounted into the battery mounting portion 5. As aresult, in the case of a camcorder 7 for business use, for example, thepower consumption is large and, therefore, only the large size batterypack 1 a having a great battery capacity can be mounted.

Other configurations than the above may also be considered. For example,the L side battery packs 1 a may be business-use batteries withcomparatively large size and capacity, while the small size batterypacks 1 b may be private-use batteries with comparatively small size andcapacity. In this case, a system may be adopted in which only the largesize battery packs 1 a can be mounted in the electronic apparatuses forbusiness use, while both size battery packs 1 a and 1 b can be mountedin electronic apparatuses for private use.

In addition, the housing 2 is provided with the detection recess(es) 50not in the front surface 2 b where a type discriminating rugged patternhas generally been provided, but at the edge(s) formed between the lowersurface 2 a and one or both of the side surfaces 2 c and 2 d. Thisensures that the housing 2 can be securely provided in its front surface2 b with a space where five terminal portions 6 and an end face of thefront surface side insertion guide groove 15 are frontingly providedside by side.

Incidentally, the battery mounting portion 5 may have a configuration inwhich type discriminating switches 52 corresponding to the detectionrecesses 50 are projectingly provided on side surfaces opposed to bothside surfaces 2 c and 2 d of the housing 2, in place of the engagingprotrusions 51. In this case, when the battery pack 1 is mounted in thebattery mounting portion 5, none of the switches 52 is pushed in thecase of the large size battery pack 1 a, whereas the switch 52 on theside surface opposed to the one side surface 2 c of the housing 2 ispushed in the case of the small size battery pack 1 b. By detecting thepushed states of the switches 52, it can be discriminated on theelectronic apparatus size which of the large size battery pack 1 a andthe small size battery pack 1 b has been mounted.

As a result, a treatment in which an alarm is issued to the user on theelectronic apparatus side, a treatment in which supply of electric powerfrom the small size battery pack 1 b is not accepted and no operation isconducted, or the like treatment can be carried out in the case wherethe small size battery pack 1 b is mounted.

Now, lock recesses 55 and 56 formed on both sides of the detectionrecess 50 in the housing 2 and operative to lock the housing 2 in thebattery mounting portion 5 will be described below. The lock recesses 55and 56 are formed on both sides of the detection recess 50 at each ofthe edges formed between the lower surface 2 a and the side surfaces 2 cand 2 d. The lock recesses 55 and 56 ensure that when the housing 2 isinserted into the battery mounting portion 5 and is slid to the mountingposition, lock protrusions 70 projectingly provided on side surfaces ofthe battery mounting portion 5 correspondingly to the lock recesses 55and 56 are locked.

As shown in FIG. 9, the front surface side lock recess 55 provided onthe side of the front surface 2 b of the housing 2 includes an inclinedsurface portion 57 for drawing in the lock protrusion 70, a clampedportion 58 to be clamped between the lock protrusion 70 and the bottomsurface 5 a of the battery mounting portion 5, and an orthogonal surfaceportion 59 continuous with the inclined surface portion 57 and extendedin the height direction substantially orthogonal to the lower surface 2a. The front surface side lock recess 55 is provided with an opening 60through which the lock protrusion 70 is put into and out of a clampedstate between the inclined surface portion 57 and the clamped portion58.

Further, the back surface side lock recess 56 provided on the side ofthe back surface 2 e of the housing 2 includes an inclined surfaceportion 61 for drawing in the lock protrusion 70, a clamped portion 62to be clamped between the lock protrusion 70 and the bottom surface 5 aof the battery mounting portion 5. The back surface side lock recess 56is provided with an opening 63 through which the lock protrusion 70 isput into and out of a clamped state between the inclined surface portion61 and the clamped portion 62.

Each of the lock protrusions 70 to be locked at the front surface sidelock recess 55 and the back surface side lock recess 56 includes a baseportion 71 provided erectingly from the bottom surface 5 a of thebattery mounting portion 5, and a lock portion 72 extended from the baseportion 71 toward the back surface side of the battery mounting portion5 and located at upper surfaces of the clamped portions 58 and 62. Thelock portion 72 is so configured that its distance from the bottomsurface 5 a of the battery mounting portion 5 is roughly equal to orslightly smaller than the thickness of the clamped portions 58 and 62 ofthe housing 2 of which the lower surface 2 a is mounted on the bottomsurface 5 a of the battery mounting portion 5. When the housing 2 isslid to the battery mounting position, the clamped portions 58 and 62are each pressed into the gap between the lock portion 72 and the bottomsurface 5 a of the battery mounting portion 5, so as to hold the clampedportions 58 and 62, thereby locking the housing 2 in the batterymounting portion 5.

When the housing 2 is inserted in the direction of an arrow D in FIG. 9until it comes to the loading/unloading position where its lower surface2 a as the mount surface abuts on the bottom surface 5 a of the batterymounting portion 5, the lock portions 72 of the lock protrusions 70 goforward through the openings 60 and 63. In this case, the inclinedsurface portions 57 and 61 and the orthogonal surface portion 59 of thehousing 2 slide on the lock protrusions 70, whereby the lock portions 72are made to be at the same height as the upper surfaces of the clampedportions 58 and 62 and are guided to such positions as to permit mutuallocking. Incidentally, the detection recess 50 is also made to goforward toward the engaging protrusion 51 projectingly provided on theside wall of the battery mounting portion 5. Next, the housing 2 is slidin the direction of an arrow S in FIG. 9, namely, toward the side of thefront surface 2 b. As a result, terminal pins 101 on the side of thebattery mounting portion 5 are inserted into and engaged with theterminal portions 6 made to front on the front surface 2 b, and theclamped portions 58 and 62 of the lock recesses 55 and 56 come to beclamped between the lock portions 72 of the lock protrusions 70 and thebottom surface 5 a of the battery mounting portion 5.

Incidentally, it suffices for the lock portions 72 to be capable ofclamping the clamped portions 58 and 62 between themselves and thebottom surface 5 a of the battery mounting portion 5, and they may notnecessarily be clamped between the upper surfaces of the clampedportions 58 and 62 and the ceiling surfaces of the lock recesses 55 and56 opposed to the upper surfaces. Therefore, a configuration may beadopted in which the lock portions 72 do not have a thickness and thatgaps are left between the lock portions 72 and the ceiling surfaces ofthe lock recesses 55 and 56. It is to be noted here that, naturally, thelock portions 72 may be clamped between the upper surfaces of theclamped portions 58 and 62 and the ceiling surfaces of the lock recesses55 and 56.

At the time of detaching (unloading) the housing 2 from the batterymounting portion 5, the housing 2 is slid in the direction opposite tothe arrow S in FIG. 9 from the mounting position to theloading/unloading position, whereby the clamped portions 58 and 62 aredrawn out of the gaps between the lock portions 72 and the bottomsurface 5 a of the battery mounting portion 5. In this instance, thelock portions 72 of the lock protrusions 70 are located in the openings60 and 63 of the lock recesses 55 and 56, so that the housing 2 can bemoved in the direction opposite to the arrow D, namely, in the directiontoward the side of the upper surface 2 f.

Here, the front surface side lock recess 55 is provided with theorthogonal surface portion 59 continuous with the inclined surfaceportion 57 and orthogonal to the lower surface 2 a. Near the orthogonalsurface portion 59, the circuit board 9 is disposed on the inside of thehousing 2. In the housing 2, the circuit board 9 is disposed at a heightwhere the inclined surface portion 57 and the orthogonal surface portion59 meet each other. Specifically, since the housing 2 is provided withthe orthogonal surface portion 59 extending in the height directionorthogonal to the lower surface 2 a, the circuit board 9 can be held onthe inside of the orthogonal surface portion 59 at the height of themeeting point between the inclined surface portion 57 and the orthogonalsurface portion 59, whereby the circuit board 9 can be disposed at theheight at which the front surface side lock recess 55 is formed.

In the large size battery pack 1 a enlarged in size and weightcorrespondingly to the business-use camcorder 7, in order to securereliability of connection between the lock recesses 55 and 56 of thehousing 2 and the lock protrusions 70 on the side of the batterymounting portion 5, it would be necessary to make the clamped portions58 and 62 thicker as compared with the related art and to form the lockportions 72 of the lock protrusions 70 to be larger as compared with therelated art. Attendant on the increase in the thickness of the clampedportions 58 and 62 and enlargement of the lock portions 72, the lockrecesses 55 and 56 are also enlarged in size in the height direction ofthe housing 2. Since the lock recesses 55 and 56 are projected to theinside of the housing 2 in the same shape, an attempt to ensure that thecircuit board 9 disposed on the lower surface 2 a side is arranged whileavoiding the projected shape results in that the lock recesses 55 and 56are naturally disposed on the upper side.

However, when it is attempted to set the circuit board 9 more on theupper side of the lower surface 2 a, the region for arranging thebattery cells 8 connected to the circuit board 9 are also disposed moreon the upper side, which leads to an increase in the size of the housing2 and, on the other hand, generates a dead space between the circuitboard 9 and the lower surface 2 a. In connection with this, when thehousing 2 has a configuration in which an increase in the size of thelock recesses 55 and 56 is contrived and the orthogonal surface portion59 is provided to thereby arrange the circuit board 9 on the inside ofthe orthogonal surface portion 59, the height at which to dispose thecircuit board 9 can be set closer to the lower surface 2 a, and thehousing 2 can be prevented from becoming larger in size. In addition,with the orthogonal surface portion 59 formed in continuity with theinclined surface portion 57, the circuit board 9 can be held at theheight of the meeting point between the inclined surface portion 57 andthe orthogonal surface portion 59, and an increase in the size of thelock recesses 55 and 56 can be attained while maintaining the area andthe arranging position of the circuit board 9. Incidentally, theorthogonal surface portion may be formed not only in the front surfaceside lock recess 55 but also in the back surface side lock recess 56.

Besides, the lock recesses 55 and 56 have the clamped portions 58 and 62formed to have a thickness larger than the depth of the detection recess50 in the height direction orthogonal to the lower surface 2 a. This canprevent the lock protrusion 70 from being erroneously inserted into thedetection recess 50 in putting the housing 2 in position.

More specifically, in the case where the lower surface 2 a is mounted onthe bottom surface 5 a without the housing 2 being guided by a side wallof the battery mounting portion 5 or the like case, the lock protrusion70 might be erroneously inserted into the detection recess 50. In thiscase, as shown in FIG. 10A, a configuration in which the depth of thedetection recess 50 is smaller than the thickness of the clampedportions 58 and 62 ensures that the housing 2 cannot be inserted to theloading/unloading position where its lower surface 2 a abuts on thebottom surface 5 a of the battery mounting portion 5 and that aninclination of the housing 2 or the like abnormality is found, whichpermits the user to recognize that appropriate insertion has not beenmade.

On the other hand, if the depth of the detection recess 50 is largerthan the thickness of the clamped portions 58 and 62, as shown in FIG.10B, the housing 2 can be inserted to the loading/unloading positionwhere its lower surface 2 a abuts on the bottom surface 5 a of thebattery mounting portion 5 even in the case where the lock protrusion 70is erroneously inserted into the detection recess 50. Asabove-mentioned, the lock portions 72 of the lock protrusions 70 arenecessary only to be capable of clamping the clamped portions 58 and 62and may not necessarily be thick, and, therefore, they can be formed ina suppressed thickness. Accordingly, where the depth of the detectionrecess 50 is formed to be larger, if only a little, than the thicknessof the clamped portions 58 and 62, the housing 2 can be inserted to thebottom surface 5 a of the battery mounting portion 5 while the lockprotrusion 70 is kept erroneously inserted in the detection recess 50.

However, in the present battery pack 1, the thickness of the clampedportions 58 and 62 is set to be larger than the depth of the detectionrecess 50, so that if the lock protrusion 70 is erroneously inserted inthe detection recess 50, the housing 2 cannot be inserted to the bottomsurface 5 a of the battery mounting portion 5. Accordingly, the user caneasily discriminate whether or not the housing 2 is erroneously insertedin the battery mounting portion 5.

Now, the depth of the detection recess 50 and the depths of the frontsurface side lock recess 55 and the back surface side lock recess 56 inthe width direction of the lower surface 2 a will be described below. Asshown in FIG. 6, the housing 2 has a configuration in which the depth ofthe detection recess 50 in the width direction of the lower surface 2 a,i.e., the depth of the detection recess(es) 50 in the lower surface 2 afrom the side surface(s) 2 c and 2 d in the direction orthogonal to thedirection of sliding of the housing 2 between the loading/unloadingposition and the mounting position, is set to be larger than the depthof the front surface side lock recess 55 and the back surface side lockrecess 56 in the same direction. As has been above-mentioned, thedetection recess 50 is for engagement with the engaging protrusion 51projectingly provided on the side wall of the battery mounting portion5. In the large size battery pack 1 a, both side surfaces 2 c and 2 d ofthe housing 2 are each provided with the detection recess 50, whereas inthe small size battery pack 1 b, only the other side surface 2 d of thehousing 2 is provided with the detection recess 50. Besides, theengaging protrusion 51 for engagement with the detection recess 50 isprojectingly provided at each of those side surfaces of the batterymounting portion 5 of the electronic apparatus used with the large sizebattery pack 1 a which face the side surfaces 2 c and 2 d of the housing2; on the other hand, the detection recess 50 is projectingly providedonly at that side surface of the battery mounting portion 5 of theelectronic apparatus used with the small size battery pack 1 b whichfaces the other side surface 2 d of the housing 2.

Each of these engaging protrusions 51 is so formed that its protrusionamount from the side surface of the battery mounting portion 5 isroughly equal to the depth of the detection recess 50 in the widthdirection of the lower surface 2 a. Therefore, when the engagingprotrusion 51 is inserted in the detection recess 50, it issubstantially entirely engaged in the detection recess 50. In addition,if a non-compatible small size battery pack 1 b is about to be insertedin the battery mounting portion 5, the engaging protrusion 51 abuts onthat one side surface 2 c of the housing 2 which is not provided withthe detection recess 50, whereby insertion of the non-compatible smallsize battery pack 1 b into the battery mounting portion 5 is prevented.

Here, the protrusion amount of the engaging protrusion 51 is set to beapproximately equal to the depth of the detection recess 50 in the widthdirection of the lower surface 2 a, and the depth of the detectionrecess 50 is set to be larger than the depth of the lock recesses 55 and56 in the same direction. In other words, the engaging protrusion 51 isformed to protrude by an amount larger than the depth of the lockrecesses 55 and 56. Besides, the lock protrusions 70 are formed to havea protrusion amount according to the depth of the lock recesses 55 and56 in the width direction of the lower surface 2 a. Accordingly, theengaging protrusion 51 is formed to have a protrusion amount larger thanthat of the lock protrusion 70.

Therefore, as shown in FIG. 11A, when the small size battery pack 1 b ismounted in the battery mounting portion 5 of an electronic apparatus forexclusive use with the large size battery pack 1 a, the engagingprotrusion 51 protruding from a side surface of the battery mountingportion 5 abuts on one side surface 2 c of the housing 2. In this case,since the engaging protrusion 51 is formed to have a protrusion amountlarger than that of the lock protrusions 70, the lock protrusions 70 arealso not inserted into the lock recesses 55 and 56. Since none of theengaging protrusion 51 and the lock protrusions 70 is engaged with thedetection recess 50 and the lock recesses 55 and 56, the housing 2cannot be mounted into the battery mounting portion 5. Therefore, in thecamcorder 7 or the like as shown in FIG. 5, for example, wherein thelower surface 2 a is inserted in a horizontal direction, the housing 2is not held by the battery mounting portion 5 even if it is beinginserted, and it is difficult to slide the housing 2 toward the side ofthe front surface 2 b. Therefore, the user can easily judge that thesmall size battery pack 1 b is being erroneously inserted into theelectronic apparatus for exclusive use with the large size battery pack1 a.

On the other hand, in the case where the depth of the detection recess50 in the width direction of the lower surface 2 a is set to be smallerthan the depth of the lock recesses 55 and 56 in the same direction, theengaging protrusion 51 on the battery mounting portion 5 side is alsoformed to have a protrusion amount smaller than that of the lockprotrusions 70. Therefore, as shown in FIG. 11B, where the small sizebattery pack 1 b is mounted in the battery mounting portion 5 of anelectronic apparatus for exclusive use with the large size battery pack1 a, the lock protrusions 70 would be inserted into the lock recesses 55and 56 even if the engaging protrusion 51 abuts on the one side surface2 c. Accordingly, it is difficult for the user to judge that erroneousinsertion of the battery pack 1 is occurring, and might irrationallyslide the housing 2 toward the front surface 2 b side so as to mount thehousing 2 into the battery mounting portion 5.

In connection with this point, in the battery pack 1 based on theembodiment according to the present invention, the detection recess 50is formed to be deeper than the lock recesses 55 and 56, so that theengaging protrusion 51 is also protruding more than the lock protrusions70, and, when the engaging protrusion 51 abuts on the one side surface 2c, the lock protrusions 70 are also prevented from being inserted intothe lock recesses 55 and 56. This ensures that, in the case of thebattery pack 1, erroneous mounting of the small size battery pack 1 binto the electronic apparatus for exclusive use with the large sizebattery pack 1 a can be prevented.

Now, the terminal portions 6 formed at a lower portion of the frontsurface 2 b of the housing 2 will be described below. As shown in FIG.12, the terminal portion 6 includes a terminal hole 80 which is formedin the lower case 4 of the housing 2 and is made to front on the outerside of the front surface 2 b, and a metallic bearing 82 which is fittedin a terminal case 81 disposed on the inside of the terminal hole 80 andin which the terminal pin 101 formed on the battery mounting portion 5side is inserted.

As shown in FIG. 13, the terminal hole 80 includes a recessed surfaceportion 84 provided with an insertion hole 83 in which the terminal pin101 is inserted, and a guide portion 85 which is formed at the innerperipheral surface of the insertion hole 83 and which is continuous withthe recessed surface portion 84 and the metallic bearing 82. Therecessed surface portion 84 is a roughly rectangularly shaped recessformed in the front surface 2 b of the housing 2, and a roughly centralportion of the bottom surface thereof is opened in a circular shape toform the insertion hole 83 in which the terminal pin 101 is to beinserted. The guide portion 85 includes an inclined surface portion 86which is formed at the inner peripheral surface of the insertion hole 83and which guides the terminal pin 101 into the metallic bearing 82, anda support surface portion 87 which is formed to be substantially equalto the metallic bearing 82 in diameter and which supports the terminalpin 101 together with the metallic bearing 82.

The insertion hole 83 opened in the recessed surface portion 84 has anupper end opened to be larger in diameter than the terminal pin 101, sothat the terminal pin 101 is easily inserted therein. Besides, theinsertion hole 83 permits the terminal pin 101 to be inserted into theterminal portion 6 without any load thereon, through a process whereinthe terminal pin 101 is guided through the inclined surface portion 86formed on the upper end side of the insertion hole 83 into the supportsurface portion 87 which is formed to be roughly equal to the metallicbearing 82 in diameter and which is continuous with the metallic bearing82.

The metallic bearing 82 disposed in continuity with the support surfaceportion 87 is a hollow cylindrical metallic member of which one end inthe longitudinal direction is opened and the other end is closed. Themetallic bearing 82 is fitted in the terminal case 81, and is connectedon its closed end side through a metallic tab 88 to the circuit board 9connected with the terminal case 81 (see FIG. 17B). As shown in FIG. 14,the metallic bearing 82 is so configured that the terminal case 81 isdisposed inside the lower case 4 together with the circuit board 9,whereby it is made to be continuous with the support surface portion 87of the terminal hole 80 as shown in FIG. 12, for insertion and holdingof the terminal pin 101 inserted in the insertion hole 83.

The terminal case 81 in which to fit the metallic bearing 82 is aroughly rectangularly shaped resin part formed to have a length in thelongitudinal direction roughly equal to the length in the widthdirection of the lower case 4. As shown in FIGS. 15 and 12, the terminalcase 81 is provided with fitting holes 89 for containing the metallicbearings 82 along the longitudinal direction thereof. The fitting hole89 has a hollow cylindrical shape with an inside diameter roughly equalto the outer shape of the metallic bearing 82, and is opened at bothends in the longitudinal direction thereof. Each metallic bearing 82 iscontinued to the terminal hole 80 via an end face of the fitting hole89, and is connected to the metallic tab 88.

In the terminal portion 6, the insertion hole 83 is opened inside therecessed surface portion 84 of the terminal hole 80, and is continued tothe metallic bearing 82 through the guide portion 85, whereby themetallic bearing 82 is located on the inner side of the housing 2relative to the front surface 2 b. This ensures that, in the terminalportion 6, it is possible to prevent short-circuiting between themetallic bearing 82 and an external metal, deformation of the metallicbearing 82 due to collision against an external portion, or the liketrouble.

In addition, in the terminal portion 6, the terminal pin 101 is insertedand held in the support surface portion 87 of the guide portion 85 ofthe terminal hole 80 and the metallic bearing 82 fitted in the terminalcase 81. With the terminal pin 101 thus inserted and held in twocomponent parts, namely, the terminal hole 80 on the lower case 4 sideand the terminal case 81 disposed inside the lower case 4, even when avibration is applied to the electronic apparatus at the time of mountingthe battery pack 1, the load exerted on the terminal pin 101 can belessened, and reliability of electrical connection can be maintained.

As shown in FIG. 16, the terminal portions 6 include first to fifthterminal portions 6 a to 6 e arrayed at a lower portion of the frontsurface 2 b. The first and second terminal portions 6 a and 6 b and thefourth and fifth terminal portions 6 d and 6 e are formed symmetricallyon left and right sides at the front surface 2 b of the housing 2, andthe third terminal portion 6 c is formed at a position deviated from thecenter of the front surface 2 b toward the side of the fourth and fifthterminal portions 6 d and 6 e. In addition, an end face of theabove-mentioned front surface side insertion guide groove 15 is made tofront on the center of the front surface 2 b.

In addition, as above-mentioned, the terminals formed at the terminalportions 6 a to 6 e have respectively predetermined functions.Specifically, the first terminal portion 6 a is a positive electrodeterminal of the battery pack 1, the second terminal portion 6 b is aclock line terminal in the SMBus line, the third terminal portion 6 c isa data line terminal in the SMBus line, the fourth terminal portion 6 dis an ID terminal with an ID resistance connected thereto, and the fifthterminal portion 6 e is a negative electrode terminal of the batterypack 1.

In using the battery pack 1, the housing 2 is inserted into the batterymounting portion 5 and is slid toward the front surface 2 b side,whereby the terminal pins 101 disposed on the battery mounting portion 5side are inserted into and held in the terminal portions 6 a to 6 e. Asa result, between the battery pack 1 and the electronic apparatus side,electric power can be supplied through the first and fifth terminalportions 6 a and 6 e; clock data can be communicated through the secondterminal portion 6 b; a variety of data such as residual batterycapacity, fully charged capacity, present charged capacity, the possibleserviceable time from now on under the present use condition, number ofcharge-discharge cycles, etc. and ID data indicating that the batterypack 1 is a genuine product, and so on can be communicated through thethird terminal portion 6 c; and the ID resistance can be detectedthrough the fourth terminal portion 6 d.

The ID resistance detected through the fourth terminal portion 6 d isused for detecting, on the electronic apparatus side, which of aplurality of types of battery packs prepared according to thedifference(s) in capacity has been mounted; specifically, differentresistances are set correspondingly to the large size battery packs 1 aand the small size battery packs 1 b. When the terminal pin 101 isinserted into the fourth terminal portion 6 d, the resistance on thebattery pack 1 side is measured, on the electronic apparatus side, andit is judged which of the different types of battery packs 1 has beenmounted.

Here, the fourth terminal portion 6 d is formed proximate to the fifthterminal portion 6 e which constitutes the negative electrode terminal.It is based on the fact that, if the ID detecting resistor and thenegative electrode line are remote from each other, electromagneticradiation from signal lines or the like therebetween is propagated asnoise, possibly hampering accurate measurement of resistance. Therefore,in the battery pack 1, with the fourth terminal portion 6 d arrangedproximate to the negative electrode terminal 6 e, the distance betweenthe ID resistor and the negative electrode line can be designed to beshort, accurate measurement of resistance can be achieved.

In addition, the third terminal portion 6 c is formed at a positiondeviated from the center in the width direction of the front surface 2 bof the housing 2 toward either of the left and right sides, in thisembodiment, toward the side of the fourth and fifth terminal portions 6d and 6 e, in view of the presence of the front surface side insertionguide groove 15 in a substantially central position in the widthdirection of the front surface 2 b.

As a result, in the battery pack 1, the terminal portions 6 a to 6 e arearranged at irregular intervals, and the terminal pins 101 formed on thebattery mounting portion 5 side correspondingly to the terminal portions6 a to 6 e are also arranged at irregular intervals, accordingly.Therefore, when the battery pack 1 is inappropriately in a left-rightreversed state, the terminal pins 101 cannot be inserted into theterminal portions, so that the battery pack 1 can be prevented frombeing erroneously inserted into the battery mounting portion 5 in theleft-right reversed state.

Besides, between the second terminal portion 6 b and the third terminalportion 6 c and between the third terminal portion 6 c and the fourthterminal portion 6 d, a pair of electrode tabs 91 connected to theelectrodes of the battery cells 8 are extended so as not to overlap withany of the third and fourth terminal portions 6 c and 6 d. As shown inFIG. 14, the electrode tabs 91 connected to the electrodes of thebattery cells 8 are formed to be narrower on the side of tip portions 91a thereof. When the battery cells 8 are contained into the housing 2,the tip portions 91 a are bent into the direction of arrows F in thefigure, before connection thereof to the circuit board 9. With thebattery cells 8 contained in the housing 2 together with the circuitboard 9, as shown in FIG. 17A, the tip portions 91 a of the electrodetabs 91 are extended in positions which are located between the secondterminal portion 6 b and the third terminal portion 6 c and between thethird terminal portion 6 c and the fourth terminal portion 6 d and whichare not on the same plane as the terminal portions 6 a to 6 e.

Incidentally, FIG. 17A is a front view showing the battery cells 8disposed on the circuit board 9 connected to a terminal case 81, andFIG. 17B is a bottom view of the same condition as viewed from the backside of the circuit board 9. As shown in FIG. 17B, the electrode tab 91is bent from an end portion of the battery cell 8 into the direction ofthe arrow F along the circuit board 9, whereby the narrower tip portion91 a thereof is laid around so as not to overlap with any of the secondto fourth terminal portions 6 b to 6 d. Therefore, in the battery pack1, it is possible to prevent electromagnetic radiations due to theelectrode tabs 91 from being propagated as noise to the communicationlines, and accurate data communication can be carried out.

Now, the battery mounting portion 5 having the terminal pins 101 to beinserted in the terminal portions 6 a to 6 e will be described below. Asshown in FIGS. 18 and 19, the battery mounting portion 5 includes aterminal board 100 having the terminal pins 101 to be inserted in theterminal portions 6 fronting on the front surface 2 b of the housing 2,a containing case 102 which contains the housing 2 therein and in whichthe terminal board 100 is fitted, and a support plate 103 for supportingthe terminal board 100 fitted in the containing case 102.

As shown in FIGS. 20A and 20B, the terminal board 100 has a roughlyrectangular overall shape, and on the side of its one surface 104fronting on the inside of the containing case 102, the terminal pins 101are projectingly provided correspondingly to the number and intervals ofthe terminal portions 6 provided on the battery pack 1 side of each ofthe terminal pins 101, the base end side is supported by a supportrecess (not shown) provided in the terminal board 100, and the tip isdirected toward the side of a front surface 100 a of the terminal board100 which faces the front surface 2 b of the housing 2. In addition,each of the terminal pins 101 is connected to a terminal cord passedthrough the support recess. Incidentally, as shown in FIG. 20B, eachterminal cord is led out to the exterior of the containing case 102through a lead-out recess 105 formed on the side of a back surface 100 bof the terminal board 100.

In addition, substantially in the center in the width direction of theone surface 104 of the terminal board 100, the above-mentioned frontsurface side guide protrusion 30 is formed adjacently to the terminalpins 101. The front surface side guide protrusion 30 is inserted in thefront surface side insertion guide groove 15 formed in the lower surface2 a of the housing 2, so as thereby to guide the loading and unloadingof the housing 2 into and from the battery mounting portion 5 and toprevent the housing 2 from chattering in the direction of both sidesurfaces 2 c and 2 d and the direction of the upper and lower surfaces 2f and 2 a when the housing 2 is mounted in the battery mounting portion5. The front surface side guide protrusion 30 is provided with the frontsurface side protruding bar 32 and the lock protrusion 33.

Incidentally, a shielding plate 106 for protecting the terminal pins 101is turnably mounted onto the one surface 104 of the terminal board 100.The shielding plate 106 is provided for preventing the terminal pins 101from contact with a conductor, breakage or the like by being exposed tothe exterior in the case where the battery pack 1 is not mounted, and isan elongate plate member disposed on the one surface 104 along the arraydirection of the terminal pins 101. The shielding plate 106 is supportedto be turnable, with the back surface 100 b side as a fulcrum. Inaddition, the shielding plate 106 is locked to a coil spring (notshown), whereby it is normally biased for turning in such a direction asto shield the terminal pins 101. This ensures that when the battery pack1 is not yet mounted, the shielding plate 106 shields the terminal pins101 from the exterior, and when the battery pack 1 is mounted, theshielding plate 106 is pushed by the front surface 2 b of the housing 2and turned toward the side of the back surface 100 b, thereby exposingthe terminal pins 101.

In addition, the terminal board 100 is provided in its bottom surface100 c with support recesses 108 brought into contact with supportprotrusions 112 of the support plate 103. The terminal board 100 issupported on the support protrusions 112 of the support plate 103, withsome clearance therebetween, whereby it is supported to be swingable inthe direction of the bottom surface 100 c. Besides, the terminal board100 is provided on its bottom surface 100 c with a lock piece 109 to belocked on the bottom surface 102 c of the containing case 102.

As shown in FIG. 21, the containing case 102 in which to contain theterminal board 100 as above is formed to be slightly larger than thehousing 2 of the battery pack 1, and has a roughly rectangular box-likeshape opened on the upper side where the housing 2 is loaded andunloaded. In addition, the containing case 102 is projectingly providedwith the above-mentioned lock protrusions 70 and the above-mentionedengaging protrusion 51 on its side walls 102 a and 102 b whichrespectively face the side surfaces 2 c and 2 d of the housing 2.Further, as shown in FIG. 8, the turning mechanism 40 for turning thelock piece 35 engaged with the lower surface 2 a of the housing 2 isdisposed at the back wall, facing the back surface 2 e of the housing 2,of the containing case 102.

The containing case 102 is provided in its bottom surface 102 c (whichconstitutes the bottom surface 5 a of the battery mounting portion 5)and both side walls 102 a and 102 b with a fitting hole 110 in which tofit the terminal board 100. The fitting hole 110 has its bottom surface102 c opened in a roughly rectangular shape, and has its side walls 102a and 102 b each opened also in a rectangular shape so as to becontinuous with the opening in the bottom surface 102 c. The terminalboard 100 is inserted into the containing case 102 through the bottomsurface 102 c, and its bottom surface 100 c is supported on both sidesthereof by the side walls 102 a and 102 b of the containing case 102,whereby the terminal board 100 is fitted in the fitting hole 110. Inthis case, the lock piece 109 of the terminal board 100 is locked on thebottom surface 102 c of the containing case 102.

As a result, of the terminal board 100, the one surface 104 providedwith the terminal pins 101 is made to front on the inside of thecontaining case 102. In addition, when the terminal board 100 is fittedin the fitting hole 110, it is supported on the bottom surface 100 cside thereof by the support plate 103.

As shown in FIG. 22, the support plate 103 is a resin part formed in aroughly rectangular plate-like shape, and is attached to the bottomsurface 102 c of the containing case 102 in a cantilever manner, therebysupporting the terminal board 100 in the fitting hole 110. The supportplate 103 is provided, on its surface facing the terminal board 100,with support protrusions 112 to be brought into contact with the supportrecesses 108 of the terminal board 100. In addition, the support plate103 is provided with an opening 113, correspondingly to the lock piece109 of the terminal board 100, and is provided with a plurality ofattaching holes 114 for attachment to the bottom surface 102 c of thecontaining case 102.

When the terminal board 100 is fitted in the fitting hole 110, thesupport plate 103 is attached to the containing case 102 from the upperside of the terminal board 100, thereby to support the terminal board100.

In this case, the support recesses 108 are formed to be wider than thesupport protrusions 112, and none of the side walls of the supportrecesses 108 makes contact with the support protrusions 112. Inaddition, the fitting hole 110 is opened on the sides of the sidesurfaces 102 a and 102 b of the containing case 102. Therefore, theterminal board 100 can be swung in the direction of an arrow X in FIG.19. The swinging range of the terminal board 100 in the direction of thearrow X is restricted by the contact of one of the side walls of thesupport recesses 108 with the support protrusion 112 or by the contactof the lock piece 109 with the opening 113.

Besides, support plate 103 is so formed as to leave some clearancebetween the tip surface of the support protrusion 112 and the bottomsurface of the support recess 108. In addition, the support plate 103 issupported on the containing case 102 in a cantilever manner, and hassome flexibility. Therefore, the terminal board 100 can be swung also inthe direction of an arrow Z in FIG. 19. The swinging range of theterminal board 100 in the direction of the arrow Z is restricted by thecontact of the bottom surfaces of the support recesses 108 with the tipsurfaces of the support protrusions 112 or by the support thereof in thefitting hole 110 formed in the side walls 102 a and 102 b of thecontaining case 102.

Further, the containing case 102 is formed as a resin part. In addition,the containing case 102 is provided with the fitting hole 110 also inits front wall 102 d, facing the back surface 100 b of the terminalboard 100, and its side walls 102 a and 102 b, whereby the front end ofthe containing case 102 is made to be a free end and to have someflexibility. Therefore, the terminal board 100 can be swung also in thedirection of an arrow Y in FIG. 19. The swinging range of the terminalboard 100 is restricted by the flexing range of the front wall 102 d ofthe containing case 102.

Thus, the battery pack 1 is so formed that the terminal board 100 can beswung in three directions, namely, in the directions of the arrows X, Yand Z in FIG. 19. This ensures that even when the battery pack 1 mountedin the battery mounting portion 5 is swung due to swinging of theelectronic apparatus main body, the terminal board 100 is swungfollowing up to the battery pack 1, keeping the terminal portions 6 andthe terminal pins 101 in connection with each other. Therefore,generation of gap at contact points between the terminal portions 6 andthe terminal pins 101 is obviated, whereby failure in connection can beprevented. In addition, sliding is prevented from occurring between theterminal portions 6 and the terminal pins 101, so that these parts canbe prevented from being broken or deteriorated.

In addition, the terminal board 100 can be swung in the direction of thearrow X in FIG. 19, since both the side walls 102 a and 102 b of thecontaining case 102 are opened. Therefore, where the battery pack 1 ismounted in the battery mounting portion 5 of the camcorder 7, theterminal board 100 can be swung in the vertical direction in which thecamcorder 7 is frequently swung. Accordingly, even if the battery pack 1is swung in the vertical direction in use of the camcorder 7, thereliability of connection between the terminal portions 6 of the batterypack 1 and the terminal pins 101 of the battery mounting portion 5 wouldnot be spoiled.

Incidentally, the battery mounting portion 5 is not limited to theconfiguration in which the containing case 102 is used for fitting theterminal board 100 and the support plate 103 therein. For example, aconfiguration may be adopted in which a battery containing portion isformed in the main body of the electronic apparatus, and the terminalboard 100 and the support plate 103 are fitted in the battery containingportion.

Now, a residual capacity displaying function of the battery pack 1 willbe described. Since the battery pack 1 is planned to be used in abusiness-use camcorder 7, the battery pack 1 is designed to have anincreased battery capacity and to be capable of being used for aprolonged time. Here, when the business-use camcorder 7 is used, aplurality of spare battery packs 1 are prepared, and when one batteryhas run down, it is replaced with another, and shooting is continued. Inthis case, the residual capacities (residual charges) of the sparebattery packs 1 are confirmed, whereby it is possible to select a sparebattery pack with more residual capacity and to discriminate unusedbattery packs from the exhausted battery pack(s) 1.

The battery pack 1 has such a residual capacity display unit 120 formedon the upper surface 2 f of the housing 2. As shown in FIGS. 1 and 23,the residual capacity display unit 120 includes display windows 121 tobe turned ON for indicating the residual capacity of the battery pack 1,a residual capacity display switch 122 for turning ON the displaywindow(s) 121, detecting means 123 for detecting the depressed state ofthe residual capacity display switch 122, and control means 124 forcontrolling the ON/OFF conditions of the display windows 121 accordingto the results of detection by the detecting means 123. The residualcapacity display unit 120 changes over the ON/OFF conditions of thedisplay windows 121 according to the time for which the residualcapacity display switch 122 is depressed, whereby the convenience in useby the user is enhanced.

The display windows 121 have LEDs incorporated therein, and the LEDs areindividually turned ON or OFF according to the residual batterycapacity. As shown in FIG. 24, for example, four display windows 121 areprovided side by side at the upper surface 2 f of the housing 2, and theON/OFF conditions of the LEDs at the display windows 121 are controlledas follows. When the residual battery capacity (absolute residualcapacity ratio) is less than 20%, all the four LEDs are turned OFF; whenthe residual capacity is 20 to 39%, only the left end LED is turned ON;when the residual capacity is 40 to 59%, the two left-side LEDs areturned ON; when the residual capacity is 60 to 79%, the three left-sideLEDs are turned ON; and when the residual capacity is 80 to 100%, allthe four LEDs are turned ON.

The residual capacity display switch 122 is formed at the upper surface2 f of the housing 2, adjacently to the display windows 121. The timefor which the residual capacity display switch 122 has been depressed bythe user is detected by the detecting means 123. The control means 124controls the ON time of the LEDs in the display windows 121, accordingto the time for which the residual capacity display switch 122 has beendepressed. For example, when the time for which the residual capacitydisplay switch 122 has been depressed is 0.5 second or less, the displaywindow(s) 121 are turned ON for 1 second; and when the time for whichthe residual capacity display switch 122 has been depressed is more than0.5 second, the display window(s) 121 are turned ON for 5 second.

The detecting means 123 for detecting the time for which the residualcapacity display switch 122 has been depressed and the control means 124for controlling the ON time of the display windows 121 are provided on acircuit board (see FIG. 2) disposed on the upper surface 2 f side in theinside of the housing 2, or on the circuit board 9 connected to thiscircuit board through a flexible wiring board.

In the residual capacity display unit 120, as shown in FIG. 25, thecontrol means 124 monitors the ON/OFF states of the LEDs (step S1).Where all the LEDs are OFF, the control means 124 determines whether ornot the residual capacity display switch 122 has been depressed (stepS2). Where the residual capacity display switch 122 has not beendepressed, the control means 124 again monitors the ON/OFF states of theLEDs, and where the residual capacity display switch 122 has beendepressed, the control means 124 determines whether or not the residualcapacity ratio of the battery pack 1 is less than 20% (step S3). Wherethe residual capacity ratio of the battery pack 1 is less than 20%, thecontrol means 124 keeps all the LEDs in the OFF state, and where theresidual capacity ratio is 20% or more, the control means 124 turns ONthe display window(s) 121 according to the residual capacity ratio,followed by returning to the monitoring of the ON/OFF states of the LEDs(step S4).

When it is found in step S1 that the LED(s) at the display window(s) 121is ON, the control means 124 determines whether or not the residualcapacity display switch 122 has been depressed for 0.5 second or less(step S5). Then, where the time for which the residual capacity displayswitch 122 has been depressed is 0.5 second or less, the control means124 determines whether or not the LED ON condition has continued for 1second (step S6). Where the LED ON condition has not continued for 1second, the control means 124 maintain the ON state of the LED(s), andwhere the LED ON condition has continued for 1 second or above, thecontrol means 124 turns OFF the LED(s), followed by returning to themonitoring of the ON/OFF states of the LEDs (step S7).

When it is found in step S5 that the residual capacity display switch122 has been depressed for more than 0.5 second, the control means 124determines whether or not the LED ON condition at the display window(s)121 has continued for 5 second (step S8). Where the LED ON condition hasnot continued for 5 second, the control means 124 maintains the LED ONcondition, and where the LED ON condition has continued for 5 second,the control means 124 turns OFF the LED(s), followed by returning to themonitoring of the ON/OFF states of the LEDs (step S9).

Thus, in the residual capacity display unit 120, the ON time of thedisplay window(s) 121 differs depending on the time for which theresidual capacity display switch 122 is depressed. For example, in thecase of sequentially checking the residual battery capacity ratios of aplurality of spare battery packs 1, it takes much time to check theresidual battery capacity ratios one by one. In such a case, therefore,the plurality of spare battery packs 1 may be arranged in a row, and theresidual capacity display switch 122 may sequentially be depressed for along time so as to turn ON the display window(s) 121 for 5 second ormore, whereby the residual capacity ratios can be confirmed efficiently.

Incidentally, the time for which the residual capacity display switch122 is depressed for the purpose of prolonging the ON time of thedisplay window(s) 121 is not limited to 0.5 second but may be changed,as required. In addition, the ON time of the display window(s) 121prolonged when the residual capacity display switch 122 is depressed fora long time is not limited to 5 second but may be changed, as required.

Besides, the change made in the ON/OFF state of the display window(s)121 when the residual capacity display switch 122 is depressed for along time is not limited to the prolonging of the ON time but may, forexample, be an increase in the luminance of the LED(s) in the displaywindow(s) 121. When the luminance of the LED(s) in the display window(s)121 is enhanced, it is possible to enhance the visibility of the displaywindows 121 in a light environment, such as outdoors in daytime.

Further, the change made in the ON/OFF state of the display window(s)121 when the residual capacity display switch 122 is depressed for along time is not limited to the prolonging of the ON time but may, forexample, be blinking of the LED(s) in the display window(s) 121, wherebyit is also made possible to enhance the visibility of the displaywindows 121. In addition, if the blinking is adopted when the ON time isprolonged, the power consumption for emitting light can be suppressed.Incidentally, the control means 124 may blink the LEDs in the displaywindows 121 also when the residual capacity display switch 122 is notdepressed for a long time, which also enhances the visibility of thedisplay windows 121.

Besides, the operation of the residual capacity display unit 120 is notlimited to the four-stage display of the display windows 121 but may beset otherwise, as required. Furthermore, where the residual batterycapacity is less than 20%, the color(s) of the LED(s) in the ON state orblinking state may be changed so as to make a display in four stages (20to 15%, 15 to 10%, 10 to 5%, and below 5%).

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. A battery pack which is loaded and unloaded toand from a battery mounting portion while sliding one surface thereofalong a sliding axis in said battery mounting portion, comprising: apair of longitudinal insertion guide grooves formed substantially in acenter of a width of a lower surface of the battery pack and extendingalong the sliding axis which is perpendicular to the width of the lowersurface, the pair of longitudinal insertion guide grooves are positionedcolinearly and spaced apart on the lower surface along the sliding axis,and provided on opposite sides of the lower surface of the battery pack,wherein each longitudinal insertion guide groove has an open end portionthat opens on a respective end side surface of a battery main body sothat the pair of longitudinal insertion guide grooves open in oppositedirections along the sliding axis, and one of the open end portions isprovided with a lock recess by which a lock piece is locked, the lockpiece being provided on the battery mounting portion and positioned soas to come in contact with the lower surface of the battery pack in thecenter of the width of the lower surface, the lock recess extends fromthe longitudinal insertion guide groove with the one of the open endportions, wherein a width and a depth of the lock recess is greater thana width and a depth of the longitudinal insertion guide groove with theone of the open end portions, the lock recess is formed on a back endside surface of the battery pack, wherein the back end side surfacefaces a direction opposite from a direction of loading the battery packto the battery mounting portion, each longitudinal insertion guidegroove is provided with an inner end portion opposite to a respectiveopen end portion, and a continuous flat section of the lower surfaceextends between the inner end portions over a substantial length of thelower surface such that the continuous flat section is longer than atleast one of the longitudinal insertion guide grooves.
 2. The batterypack as set forth in claim 1, wherein the other of the open end portionsextends from the longitudinal insertion guide groove that is on therespective end side surface that is a front end side of the batterypack, the other of the open end portions is substantially L-shaped andopens on the front end side surface in a direction of loading thebattery pack to the battery mounting portion.
 3. The battery pack as setforth in claim 1, wherein an identification label is adhered to the onesurface.
 4. The battery pack as set forth in claim 1, wherein a circuitboard is disposed on an inside surface side in the battery main body. 5.The battery pack as set forth in claim 1 further comprising, a firstside surface extending along a first plane that is perpendicular to theend side surfaces; a second side surface extending along a second planethat is perpendicular to the end side surfaces; and a first side lockrecess formed at an edge between the lower surface and one of the firstside surface and the second side surface including a clamp portion, aninclined surface portion, and an orthogonal surface portion that extendscontinuously from the inclined surface portion.
 6. The battery pack asset forth in claim 1 further comprising, a first side surface extendingalong a first plane that is perpendicular to the end side surfaces; asecond side surface extending along a second plane that is perpendicularto the end side surfaces; and a first detection recess for detecting aswitch on the battery mounting portion, wherein the first detectionrecess is formed at an edge between the lower surface and one of thefirst side surface and the second side surface.
 7. The battery pack asset forth in claim 6 further comprising, a first side lock recess formedat an edge between the lower surface and the one of the first sidesurface and the second side surface including the first detectionrecess, wherein the first side lock recess is located along the one ofthe first side surface and the second side surface including the firstdetection recess between the first detection recess and one of the endside surfaces, wherein the first side lock recess includes a clampportion, an inclined surface portion, and an orthogonal surface portionthat extends continuously from the inclined surface portion.
 8. Thebattery pack as set forth in claim 1, further comprising anidentification label adhered to the continuous flat section of the lowersurface between the inner end portions.